Validation of the Microsoft Kinect® camera system for measurement of lower extremity jump landing and squatting kinematics

Cost effective, quantifiable assessment of lower extremity movement represents potential improvement over standard tools for evaluation of injury risk. Ten healthy participants completed three trials of a drop jump, overhead squat, and single leg squat task. Peak hip and knee kinematics were assessed using an 8 camera BTS Smart 7000DX motion analysis system and the Microsoft Kinect® camera system. The agreement and consistency between both uncorrected and correct Kinect kinematic variables and the BTS camera system were assessed using interclass correlations coefficients. Peak sagittal plane kinematics measured using the Microsoft Kinect® camera system explained a significant amount of variance [Range_hip = 43.5–62.8%; Range_knee = 67.5–89.6%] in peak kinematics measured using the BTS camera system. Across tasks, peak knee flexion angle and peak hip flexion were found to be consistent and in agreement when the Microsoft Kinect® camera system was directly compared to the BTS camera system but these values were improved following application of a corrective factor. The Microsoft Kinect® may not be an appropriate surrogate for traditional motion analysis technology, but it may have potential applications as a real-time feedback tool in pathological or high injury risk populations.     

Alterations in autonomic cardiac modulation in response to normobaric hypoxia

Purpose: The present study aimed to determine if autonomic cardiac modulation was influenced by acute exposure to normobaric hypoxia. Method: Ten healthy male lowland dwellers completed five block-randomised single-blinded, crossed-over acute exposures to a normobaric hypoxic environment, each separated by 24 hours’ recovery (20.3%, 17.4%, 14.5%, 12.0% and 9.8% F_IO₂). Supine recordings were made of arterial oxygen saturation and electrocardiogram (ECG). RR intervals from the ECG trace were analysed for time (SDNN, lnrMSSD), frequency (lnVLF, lnLF, lnHF, lnTP, LFnu, and HFnu), and nonlinear (DFA-α1 and SampEn) heart rate variability components. Results: A significant reduction in arterial SaO₂ occurred with reduced F_IO₂, along with a rise in heart rate (Cohen’s d?=?1.16, 95% Confidence Interval [2.64–6.46]), significant at 9.8% F_IO₂. A decrease in autonomic cardiac modulation was also found as shown by a statistically significant (at 9.8% F_IO₂) decrease in lnTP (d?=?1.84 [1.74–1.94]), and SampEn (d?=?0.98 [0.83–1.12]) and an increase in DFA-α₁ (d?=?0.72 [0.60–0.84]) from normoxia at 9.8% F_IO₂. Conclusion: The decrease in variability indicated a reduction in autonomic cardiac modulation. There appears to be a threshold ～9.8% F_IO₂ (～6000?m equiv.), below which significant alterations in autonomic control occur.     

Comparison of three web-scale discovery services for health sciences research

Objective

The purpose of this study was to investigate the relative effectiveness of three web-scale discovery (WSD) tools in answering health sciences search queries.

Methods

Simple keyword searches, based on topics from six health sciences disciplines, were run at multiple real-world implementations of EBSCO Discovery Service (EDS), Ex Libris''s Primo, and ProQuest''s Summon. Each WSD tool was evaluated in its ability to retrieve relevant results and in its coverage of MEDLINE content.

Results

All WSD tools returned between 50%–60% relevant results. Primo returned a higher number of duplicate results than the other 2 WSD products. Summon results were more relevant when search terms were automatically mapped to controlled vocabulary. EDS indexed the largest number of MEDLINE citations, followed closely by Summon. Additionally, keyword searches in all 3 WSD tools retrieved relevant material that was not found with precision (Medical Subject Headings) searches in MEDLINE.

Conclusions

None of the 3 WSD products studied was overwhelmingly more effective in returning relevant results. While difficult to place the figure of 50%–60% relevance in context, it implies a strong likelihood that the average user would be able to find satisfactory sources on the first page of search results using a rudimentary keyword search. The discovery of additional relevant material beyond that retrieved from MEDLINE indicates WSD tools'' value as a supplement to traditional resources for health sciences researchers.     

Gender differences in the academic career

This study examines sources of satisfaction, indicators of stress, academic performance, and reward structure in the academic careers of male and female faculty at a major midwestern state university. Faculty pairs were selected from five academic divisions. A total of 58 matched pairs were identified. Of these, 63 faculty responded, yielding data for 23 matched pairs. Subjects were mailed the Academic Career Development Survey, consisting of 144 items. Results indicated that self-reported physical and mental health, and professional and personal life satisfaction were high for both males and females. Both males and females placed high importance on their career and on marriage/other intimate relationships; however, both reported high levels of dissatisfaction with these factors. Gender differences were found in both satisfaction and type of stress reported; no gender differences were found in composite teaching and research performance indices. Salary data, obtained for 42 matched pairs, indicated similar salary levels for men and women. Results were discussed with respect to prior research on gender differences and the academic career.     

Disruptive silence: deepening experiential learning in the absence of technology

Technology plays an integral role in the lives of the majority of the US population. As technology becomes integrated into young people’s lives, questions arise regarding its effects on learning. This exploratory study draws on interviews with students who attend university in the United States to determine how separating students from technology deepens experiential learning. Participants were interviewed following a study abroad course to New Zealand, during which they were disconnected from technologies such as cell phones, the Internet and social media. In the interviews, students discussed their feelings of being disconnected and describe how disconnecting impacted their overall experience. Participants agreed that disconnecting from technology had positive effects on experiential learning and the global experience. Major themes that emerged include students’ enhanced immersion and engagement, the value of disconnection in providing opportunities for personal growth and the difficulty of initial separation from technology as a result of conditioning.     

The relationship between individual instructional characteristics and the overall assessment of teaching effectiveness across different instructional contexts

There is an ongoing debate in the student evaluation of teaching literature about whether an overall rating or factorial dimensions of teaching effectiveness should be used in personnel decisions. Marsh and his colleagues have advocated the use of a weighted average approach to computing overall evaluations. A policy-capturing experiment was carried out where students in three different instructional contexts made overall evaluations of hypothetical instructors based on a manipulation of the teaching factors in Marsh's SEEQ. The results indicated (1) amount learned was consistently the most important factor affecting overall evaluations; (2) course difficulty was consistently the least important factor affecting overall evaluations; and (3) there was a strong similarity among the three groups in the relative importance of the various teaching factors in arriving at an overall evaluation. The implications of this research are discussed, as well as directions for future research.     

A comparison of the dimensions used by Iranian and American students in rating instruction

This study investigated the dimensions of teacher behavior and classroom characteristics used by Iranian high school students (N=880) in evaluating their classroom experience. Secondly, it compared these dimensions to those used by American high school students (N=599). During January, 1978, both groups of students completed the Classroom Behavior Survey (CBS). Principal components analysis with varimax rotation yielded a 12 factor solution for Iranian data and 14 for the American data. Comparison of the factors suggest that the dimensions on which Iranian and American students evaluate their teachers are substantially different, though the dimensions they use to evaluate characteristics of the course and content are similar.

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Zusammenfassung Diese Studie untersucht die Dimensionen von Lehrerverhalten und Unterrichtsweisen, die iranische Studenten zur Evaluation ihrer Klassenerfahrungen angewandt haben. Ferner vergleicht sie diese Dimensionen mit den von amerikanischen Sekundarschülern benutzten. Beide Schülergruppen beendeten ihre Untersuchungen über Unterrichtsverhalten im Januar 1978. Eine Analyse der Hauptkomponenten, mit Varimax Rotation, ergab eine 12-Faktorenlösung für die iranischen Daten gegenüber 14 Faktoren für die amerikanischen. Ein Vergleich dieser Faktoren deutet darauf hin, daß die Dimensionen, aufgrund derer die iranischen und amerikanischen Schüler ihre Lehrer bewerten, stark voneinander abweichen, während sich die für die Beurteilung der Kurse und Inhalte gebrauchten gleichen.

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Résumé Cette étude porte sur les cotes du comportement de l'enseignant et des caractéristiques de la classe utilisées par les élèves iraniens de l'enseignement secondaire. (N=880) dans leur évaluation de leur expérience scolaire. Elle compare ensuite ces cotes à celles utilisées par les élèves américains du secondaire. Les deux groupes d'élèves ont terminé leur enquête sur le comportement de la classe (CBS ECC) en janvier 1978. L'analyse des principales composantes avec rotation varimax a donné une solution à 12 facteurs pour les données iraniennes et à 14 facteurs pour les données américaines. La comparaison des facteurs suggère que les cotes selon lesquelles les élèves iraniens et américains évaluent leurs enseignants sont notablement différentes, bien que celles qu'ils utilisent pour évaluer les caractéristiques du cours et de son contenu soient similaires.

     

The Performance of the Mantel-Haenszel Procedure Across Samples and Matching Criteria

This study examined the reliability of the Mantel-Haenszel indexes across different samples of test takers as well as across sample sizes and investigated whether these indexes are robust to item context effects. Mathematics data from the Second International Mathematics Study (SIMS; 1985) for U.S. eighth-grade students were analyzed. The results suggest that the MH D-DIF is robust to item context effects. However, larger sample sizes than those used in this investigation (N = 141-167 for the focal group) may be necessary to obtain stable estimates from the Mantel-Haenszel procedure.     

Who are Rural Students? How Definitions of Rurality Affect Research on College Completion

Research in Higher Education - Given a revived national discourse about rural populations, more educational research on rural students is necessary, including ways that rural students transition to...